Vapor Intrusion of Contamination
From Soil and Groundwater
Into
Indoor Air

Viewpoints from a Public Hearing

Assemblyman Thomas P. DiNapoli, Chairman
New York State Assembly Committee on Environmental Conservation

March 2005

Introduction

Contamination of indoor air by volatile chemicals from contaminated soil and groundwater is an emerging
area of public health concern. Vapor intrusion occurs when contaminants vaporize and rise up through
cracks, gaps, or pores in soil and foundations into homes and other buildings. Vapor intrusion is known
to have occurred at several Superfund sites in New York State and has the potential to be a problem at
brownfield sites as well. While the New York State Department of Environmental Conservation (DEC)
and the Department of Health (DOH), as well as the United States Environmental Protection Agency
(EPA), have issued draft guidance pertaining to various aspects of vapor intrusion, none have been
finalized.

On November 15, 2004 the Assembly Environmental Conservation Committee convened a public
hearing in Endicott, New York to examine issues concerning vaporization and resulting human
exposure. The primary purpose of the hearing was to determine what lessons can be learned from
past experience in order to properly address vapor intrusion in the future. The Committee received
testimony from panels of witnesses including federal, state and local government officials,
public health and environmental experts, and citizens representing affected communities.
This report provides a summary of testimony received at the hearing and recommendations for
future action.

Background

While federal and state agencies have been aware of the potential for vaporized contaminants to enter into
homes and buildings for over a decade, conventional wisdom held that levels of indoor air contamination
would not be of concern due to dilution and attenuation. Experts in environmental health and engineering
have only recently come to realize the true potential for vapor intrusion to result in widespread human
exposures. Indoor air sampling performed at a site in Colorado in 2000-2001 found significant levels
of the contaminant trichloroethylene (TCE) in homes where the computer model recommended by EPA
had predicted little or no contamination. As a result, EPA and state agencies began a national effort to
understand vapor intrusion and to revisit sites where cleanup has occurred but the potential for vapor
intrusion is high.

Here in New York, this effort led to the discovery of widespread contamination in Endicott, which now
has mitigation systems in place in over 450 homes and businesses. Vapor intrusion has also been
discovered in Hopewell Junction, which EPA proposed for listing on the National Priorities List (NPL)
on September 23, 2004 pursuant to federal Superfund. At Hopewell, EPA collected soil gas samples
at 206 homes and found detectable concentrations of TCE at 65 of those homes. Sub-slab ventilation
systems have been installed at 42 of the 65 homes. Vapor intrusion problems have also been identified
in Hillcrest, at the Jackson Steel site in Long Island, at the Morse Industrial Corporation site in Ithaca,
as well as at several other sites around the state.

The issue of vapor intrusion poses serious challenges for sound public policy making in New York
State as well as nationally. The biggest of these challenges is the lack of clear health and environmental
standards for indoor air pollution. This is especially true for TCE, the most common volatile chemical found
at thousands of contaminated sites across the country. TCE is the chemical of greatest concern at the
Endicott, Hopewell Junction, and Hillcrest sites. The level of TCE contamination considered protective
of human health varies widely across EPA regions and states, causing concern to citizens and regulatory
agencies alike.

A number of other challenges posed by vapor intrusion must also be addressed. They include:

How to determine which sites and/or buildings have the potential to be contaminated by
vapor intrusion and should be tested;

Following preliminary investigations, how to determine which sites and/or buildings
have contamination problems serious enough to investigate further and/or mitigate;

How to proceed with the mitigation of buildings with problems;

Whether current mitigation systems are adequate to protect public health over the
long term, and how to ensure the proper monitoring and maintenance of such systems; and

Whether mitigation alone is sufficient, or whether more extensive remediation
is needed to eliminate the source of contaminants.

Status of Current Standards and Regulation

EPA is in the process of developing guidance for evaluating vapor intrusion. This guidance
was designed only to determine if there is a potential for an unacceptable risk, not to provide
recommendations on how to delineate the extent of risk or how to eliminate the risk. The
guidance will not resolve the lack of national standards for contaminants in indoor air. EPA’s
Office of Solid Waste and Emergency Response released the draft guidance in the November 29, 2002
Federal Register and is currently reviewing the numerous comments received. Two technical sessions
have been held to review the draft guidance and a third is planned for March 2005. It is uncertain when the
guidance will be finalized.

In 2001, EPA released a draft toxicity assessment for TCE based on current information regarding toxicity
and health effects. Significantly, the draft assessment found that children are more susceptible to TCE
exposure than adults and that TCE is five to 65 times more toxic than was previously believed. The TCE
toxicity assessment was peer reviewed by EPA’s Science Advisory Board, which recommended
finalization of the assessment with some revisions. In response to concerns raised by the Department
of Defense, however, EPA requested additional external peer review by the National Academy of Sciences.
The Academy officially initiated its review of the draft assessment in December 2004. It is expected to take
about 15 months.

In the meantime, some states and EPA regions have adopted more stringent TCE exposure and remediation
guidelines based on the analysis provided in the draft assessment. In the absence of a definitive toxicity
assessment, the TCE guidelines adopted by Regions and states vary significantly, by an order of magnitude or
more. For example, EPA Regions 3 and 6 adopted TCE air guidelines based on the most conservative
assumptions provided in the draft toxicity assessment. At 0.016 micrograms per cubic meter
(mcg/m3) and 0.017 mcg/m3
respectively, these guidelines are among the most stringent in the country, and correspond to one excess lifetime
(30-year) cancer among a million people. Colorado has adopted 0.016 mcg/m3
as the level at which screening will occur and 1.6 as the level at which cleanup will be required. EPA Region 9
presented two values, 0.017 and 0.96, in their "Preliminary Remediation Goals Table" published in
October 2004. An explanation of the 2004 Table states, "Region 9 has shown both [TCE values] on this
Table, rather than choosing one over the other, to give Table users as much information as possible in the
absence of a final EPA toxicity value." The State of California has a "Target Indoor Air
Concentration" of 1.22 mcg/m3 based on a much less conservative
toxicity assumption than those contained in EPA’s draft assessment (See Appendix F for a table showing the
range of TCE values employed by various EPA Regions and states).

In October of 2003, DOH established an air guideline for TCE of 5 mcg/m3,
which is significantly higher than California, Colorado, and several EPA Regions. This guideline is the subject of
much debate, and DOH is currently in the process of establishing a panel of experts to provide peer review for the
guideline. The promulgation of the new TCE guideline has resulted in the inconsistent treatment of homes in
Endicott. Before October 2003, vent systems were installed in homes where TCE was detected at levels above
0.22 mcg/m3. However, under the new guideline, homes tested after
October 2003 only qualify for vent systems if TCE is detected at levels above the
5 mcg/m3 threshold. This has led to confusion and frustration within
the affected community.

In late 2004, DEC issued a draft Program Policy titled "Evaluating the Potential for Vapor Intrusion at Past,
Current, and Future Sites." This draft policy states that DEC has compiled a list of 400 State Superfund sites
at which chlorinated volatile organic compounds (CVOCs) have been disposed or detected in groundwater and
750 sites with groundwater contaminated by volatile organic compounds (VOCs). Under the policy, these sites would be
evaluated and ranked for further investigation and potential remediation. The public comment period on the draft policy
ended on January 24, 2005. The draft policy left several concerns that will hopefully be addressed before the policy is
finalized, including the number of sites to be investigated, how long it will take, and what level of exposure will trigger
remediation (See Appendix D for the full text of Assemblyman DiNapoli’s comments on the
draft policy).

DOH has also issued draft guidance on vapor intrusion titled "Guidance for Evaluating Soil Vapor Intrusion in
the State of New York." The draft was released on February 21, 2005. The public comment period ends
April 23, 2005.

In New York State, a new Brownfield Cleanup Program (BCP) was enacted in October of 2003. The law provided for the
voluntary cleanup of brownfield sites, refinancing of the State Superfund program, and the creation of a comprehensive
program for the long-term restoration of groundwater. Under the BCP statute a new Groundwater Protection and
Remediation Program was created, the provisions of which are based on experience under the Superfund and
Oil Spill cleanup programs. The program provides for the long-term pursuit and remediation of groundwater
contamination that has migrated off-site. The law also requires the provision of opportunities for meaningful
public participation, and establishes a Technical Assistance Grants Program for both Superfund and brownfield
sites, something that will be particularly important at vapor intrusion sites.

Summary of Testimony

The following are summaries of testimony presented at the hearing or submitted for the record.
These summaries were prepared either by the witness or by staff using their written testimony. Copies
of the written testimony may be obtained by contacting the Committee.

Honorable Maurice Hinchey, Congressman, 22nd District

This hearing is an important step towards assessing how regulatory agencies have dealt with Endicott’s
toxic contamination and how to improve procedures for dealing with the emerging threat that vapor intrusion
presents in communities statewide.

As I learned of the extensive toxic plume beneath Endicott, I immediately pushed for a comprehensive health
study as well as expedited remedial action. While progress has been made on both these fronts -- a health study
is underway and the site has been reclassified from Class 4 (site which has been properly closed but requires
continued management) to Class 2 (site which poses a significant threat to public health or the environment
and requires action) on the New York State Registry of Inactive Hazardous Waste Sites -- there is more to be
done.

Some of the unresolved issues concerning this site include:

Shoddy regulatory record keeping, particularly the absence of a consent order between IBM and DEC -- which
should have been established in the 1980s;

The positive identification of the polluter primarily responsible for releasing toxic chemicals. To date some
80,000 gallons of toxic chemicals have been removed, yet IBM has admitted to releasing only 4,100 gallons;

The status of the historical records reportedly maintained by IBM which track employee mortality rates; and

The remediation timeline and whether the Consent Order entered in August 2004 will serve as the
guiding document, or will be superceded by a Record of Decision.

TCE inhalation and drinking water standards are presently under review by the federal government.
The progress of this review should be followed closely and may have a profound impact on remediation
efforts in Endicott and elsewhere.

Honorable Joan Pulse, Mayor, Village of Endicott (Edited by staff)

The Village of Endicott has encountered numerous trials and tribulations throughout the years. Although we
have faced challenges, we were still able to seize and capitalize on every opportunity that was presented
before us.

During my campaign and since election, I have had three primary goals for the Village of Endicott: fiscal
responsibility, economic development (which will create and secure the future for our children), and safety
(specifically addressing any and all environmental concerns in our community). Protecting our community,
and holding accountable those responsible for the contamination, is fundamental to my
beliefs-THOSE WHO DID IT; CLEAN IT UP!

Five years ago, no one had ever heard of vapor intrusion. A situation in Colorado shed new light on our
understanding of vapor intrusion. EPA continues to work diligently to help others understand the
environmental impacts of this emerging issue.

State and local agencies have met with residents on numerous occasions, provided information,
conducted investigations, and where appropriate, ensured that responsible parties are held accountable
for cleanup. I, and the residents of the Village of Endicott, would accept no less. I would argue that Endicott,
from the environmental perspective, is one of the most highly scrutinized municipalities in the State, if not the
Nation.

I welcome and endorse the need to protect our citizens. I personally have said and will continue to say, "I
will hold IBM’s feet to the fire" when it comes to protecting our environment - but I refuse to accept
the portrayal by the media that every effort isn’t being made to address the situation. Yes, there are
environmental concerns in Endicott and they do need to be resolved. There needs to be oversight, to ensure the
protection of citizens - and that is being done by the DEC and the State and County DOH.

I rely on and thank the DEC and the State and County DOH. Moving forward, protecting residents, improving the
quality of life, and providing opportunities are the responsibilities of my administration. I encourage those present
to join me in accomplishing these goals, and I again thank the committee for taking up this issue.

Along with the New York State Department of Health (DOH), the Department of Environmental Conservation
(DEC) is committed to protecting public health and environmental quality from the potentially serious effects
of vapor intrusion into homes and businesses.

Vapor intrusion is a rapidly developing field of science and policy. While chemical concentrations of vapors
are typically low, in some instances they can accumulate to levels which pose safety hazards, including the
potential for explosions or acute health effects. Even in low concentrations, these vapors may lead to chronic
health effects.

Determining the exact concentrations of contaminants in a building resulting from vapor intrusion may be
difficult. For example, the use of other substances (including gasoline and cleaning solvents) in or around
a building may complicate our ability to effectively determine the precise level and source of contaminants
stemming from vapor intrusion. Through modeling and direct measurements, DEC makes the best possible
estimate of actual contamination levels resulting from vapor intrusion. In partnership with DOH, we then
search for means to resolve the problem.

DEC recognizes that vapor intrusion cannot be resolved simply through ventilation at the buildings where
hazardous or potentially hazardous levels of vapors are discovered. Elimination of the source is our ultimate
objective. We view the use of vapor mitigation systems as a short-term solution to the vapor intrusion problem.
By addressing the source of the contamination, and ensuring that steps are taken to remediate and monitor the
soil and groundwater which provides a pathway for the migration of these chemicals, DEC can provide effective
long-term protection of the public health from vapor migration.

The standards with which cleanups must comply are determined by DOH, not DEC. Our responsibility involves
establishing a cleanup plan which ensures that contamination is cleaned up to the level established by DOH.

DEC has developed a program policy to deal with all sites in all the remedial programs where vapor intrusion
may be an issue. The strategy in the policy divides the universe of sites into two groups: 1) sites where remedial
decisions have already been made (legacy sites) and 2) sites where remedial decisions have yet to be made.
The guidance in this document primarily applies to the first group - sites where decisions have already been
made - and outlines a process to be used to identify and prioritize those sites for further action. A prioritization
approach has been developed to focus efforts on evaluation of legacy sites with the greatest potential for vapor
intrusion first. DEC is in the process of working through the universe of legacy sites in order to identify the sites
of concern. The sites in group 2 have already been evaluated and, where necessary, vapor intrusion is being
added as part of a routine investigation. All future sites will include a vapor intrusion investigation component.

The remediation of vapor intrusion sites is complex, and these comments only provide a brief synopsis of the
actions which DEC undertakes.

The New York State Department of Health (DOH), in conjunction with other state and federal agencies, is
carrying out a number of activities related to vapor intrusion, including the performance of environmental
health investigations and health studies; the development of remedial guidance, guidelines for chemicals
in air, and soil cleanup objectives for brownfields; and the provision of public health information.

Environmental health investigations at vapor intrusion sites follow an approach consistent with that for other
environmental media. Since no two sites are exactly alike, the approach is dependent on site specific
conditions, including site use history, geological and other physical characteristics, and potentially exposed
populations. Existing information is reviewed and new data is gathered until questions regarding current
and potential exposures and the actions needed to prevent or mitigate exposures and remediate the source
of vapor contamination can be answered.

DEC and DOH are drafting guidance right now for investigating and evaluating exposure pathways, an early
draft of which is attached to our testimony.

DOH is also developing an approach to making remedial decisions based on soil vapor and indoor air
concentrations. The approach is outlined in a matrix and to date matrices have been developed for
trichloroethylene and tetrachloroethylene. Drafts are being provided with our testimony for you to comment
on however you want to. The form of the matrix is evolving as we learn more and apply it at different sites.

In addition, DOH has developed indoor air guidelines for the drycleaning chemical tetrachloroethylene
(also known as perc), dioxin, PCBs and TCE. The TCE guideline was established after an extensive
evaluation of scientific information using methods consistent with those used by other agencies and
scientific bodies. We looked at both cancer and non-cancer effects and focused most on inhalation studies.
We developed potential guidelines or criteria for evaluating TCE toxicity for all the different health effects, and
in general, those guidelines range from one to ten micrograms per cubic meter of air. The guideline adopted
is five micrograms per cubic meter of air.

We developed the TCE guideline based on our understanding of the science. We reviewed EPA’s draft
Toxicity Assessment for TCE and the Science Advisory Board’s review, which provided many
recommendations for improving the document and many more details about the uncertainties involved
in estimating TCE’s cancer risks. Depending on the various aspects of TCE at issue, we came up
with a slightly different answer than the Assessment. We also looked at critiques of the Assessment by
some other EPA scientists who are aware of California’s work on TCE.

Some EPA regions have taken a lower figure and some reference concentrations are higher. It depends on
which guideline you look at. For example, the cancer potency factor for TCE in air recommended by EPA
Region 3 is the highest recommended by EPA in the draft Assessment. It is based on an epidemiological
study with the following limitations: the study did not have individual exposure measurements; the study
population was exposed to other chemicals besides TCE; and the routes of exposure for the study were
ingestion, and probably dermal absorption and inhalation, as compared to inhalation alone.

Our guideline corresponds to an excess cancer risk of between one in one million and one in one hundred
thousand, depending on the risk extrapolation relied upon. But it is generally probably a little bit greater than
one in one million.

We have committed to a peer review process for the TCE guideline and expect to ask various stakeholders to
recommend scientists for the peer review. For the peer review, we are completing an extensive scientific
document about the key issues related to TCE toxicity and risks. We also recognize the need to continue
to update, review and refine our evaluation of the potential health risks associated with TCE using good
science.

EPA considers vapor intrusion from contaminated soils or groundwater into homes and other buildings to be
a significant environmental concern and one where the science is still evolving. We have long recognized that
volatile organics contaminating soils or groundwater can migrate into nearby buildings, resulting in indoor air
levels that may present a human health threat. Within recent years, however, we have come to recognize that
the occurrence of vapor intrusion into buildings is more widespread than previously thought. For example, in
some cases, volatile organics have migrated further from their source than was expected; in others, vapor
intrusion was not originally identified as an exposure pathway of concern, but later proved to be one.

Because we now recognize the potential for vapor intrusion to be a significant exposure pathway at certain
remediation sites, EPA and state environmental agencies have paid increased attention to indoor air
concerns at cleanup sites where soil or groundwater is contaminated with volatile organics. For example,
in the Resource Conservation and Recovery Act (RCRA) corrective action cleanup program, we routinely
screen sites for potential vapor intrusion where there is a possible concern. Where concerns are identified,
EPA (or more frequently under RCRA, the authorized state agency) requires corrective action - for example,
the installation of vapor removal systems beneath a building.

Perhaps the most difficult challenge relating to vapor intrusion is determining with reasonable certainty
whether there is likely to be a problem or not when buildings are in the vicinity of soil or groundwater
contaminated with volatile organics. A complicating factor in evaluating vapor intrusion and the risks it may
pose is the potential presence of some of the same chemicals at or above background concentrations from
the ambient (outdoor) air and/or emission sources in the building e.g., household solvents, gasoline, cleaners.
Because of the large number of sites where vapor intrusion could potentially be a concern, because the science
is still evolving in this area, and because of the technical difficulties in determining whether there actually is a
problem at a given location, the EPA Office of Solid Waste and Emergency Response developed draft screening
guidance, which it published for comment on November 29, 2002 (Federal Register November 29, 2002:
67 FR 71169-71172).

In this draft guidance, EPA recommends a tiered approach to screening sites for vapor intrusion potential - that is, to
determine whether vapor from volatile organics is likely to be entering buildings, and if so whether it would likely be a
health concern. The guidance recommends that regulators and responsible parties use a conservative modeling
approach in determining whether there is likely concern at a given location, and that they conduct sub-slab and
indoor air sampling when the possibility of vapor intrusion at levels of concern can’t be ruled out. The
guidance also notes that when indoor air sampling is conducted, that it be conducted more than once and the
sampling program be designed to identify ambient and indoor air emission sources of contaminants.

EPA received numerous comments on this guidance, which it is now reviewing. We have held technical working
sessions with the states, academia, and external stakeholders to discuss this guidance in San Diego, California
and Amherst, Massachusetts, and will be returning to San Diego next March for our third technical working session.
After that meeting, we will determine how best and over what time period to finalize the guidance.

When it published this draft guidance, EPA recommended its use at RCRA, Superfund, and Brownfield cleanup sites.
However, we emphasize that it is only guidance and is still in draft form, and that other approaches may also be
appropriate. Furthermore, the State of New York is authorized to run the RCRA cleanup program in lieu of EPA,
and therefore the New York State Department of Environmental Conservation is generally responsible for overseeing
and regulating RCRA cleanups within the state. New York-like any authorized state under RCRA-may choose to follow
this guidance, or may adopt other approaches that achieve protective results.

Joseph Graney, Ph.D., Assistant Professor, Dept. of Geological Sciences and Environmental Studies, State
University of New York at Binghamton (Edited by staff)

I have been fortunate to have been involved in some of the scientific research related to the Hillcrest problems.
Much of my work at Hillcrest has been related to the emission and transport of vapor phase mercury. I believe that
similarities in the chemical and physical properties of mercury to volatile organic compounds (VOCs) may allow
findings from mercury monitoring studies to act as a potential surrogate for designing future studies of VOCs in
brownfields as well as residential exposure studies.

The methods for detecting indoor air concentrations of organic compounds such as trichloroethylene (TCE) and
other VOCs typically require use of Summa canisters and relatively long sampling times (typically 24 hours).
Collection and analysis of such samples is expensive, but needed for regulatory purposes including exposure
assessments. However, short term monitoring times and in-situ sampling methods would be of major benefit
to better determine shorter term variation in VOC concentrations from exposure perspectives. Such instrumentation
is available for monitoring low level mercury concentrations in indoor air exposure settings, and further development
of similar instrumentation for low level VOCs is needed. Such instrumentation could be used to quickly screen
large numbers of residences in a cost effective manner.

The times of year when samples should be collected for indoor and ambient air exposure assessments need
further study. I am not convinced that the major indoor air exposure to contaminants associated with vapor intrusion
occurs during the winter months (i.e. during the heating season when forced air furnaces are in operation). Sampling
during all seasons should be carried out to document temporal trends in VOC concentrations specific to the climatic
conditions in the Southern Tier of New York State.

The complex terrain of the Southern Tier (characterized by incised river valleys and surrounding hilltops) may make
ambient air quality from venting of VOCs in residential areas a concern, due to the likelihood of pollutants being
preferentially channeled within the river valleys. Methods should be devised and tested to lower the VOC emissions
to ambient air. For example, the installation of in-situ VOC vapor adsorption cartridges inside ventilation ductwork
may lower emissions to ambient air.

Groundwater contamination problems are proving to be difficult to rectify. There may be need for a further evaluation
of innovative groundwater remediation approaches above and beyond conventional pump and treat methods. The
study of preferential pathways of groundwater and vapor phase pollutant transport in relation to underground utility
services (gas, sewer, cable, electric, telephone) is also in need of further study.

U.S. EPA’s 2001 draft toxicity assessment found that TCE is five to sixty-five times more toxic than
previously believed, largely because of the risk to children. Consequently, most EPA Regions have adopted
a new "provisional" standard of .017 micrograms per cubic meter (mcg/m3). However, New York
has no clear plan for responding at concentrations below 5 mcg/m3. Because people who live and work above
volatile pollution cannot replace the air they breathe, policy-makers should take a more precautionary approach.

Vapor intrusion is usually viewed as the rise of toxic fumes directly into structures. However, contamination may
escape over a large area, elevating ambient concentrations above the screening level. Therefore, investigations
should be based upon conceptual site models that consider all sources, pathways, and receptors.

Cleanup should be accelerated to ensure that mitigation measures will remain effective in the long run, reduce
outdoor exposures, and enable safe reuse of vapor-impacted properties. Today there are cheaper, faster technologies
that can protect against vapor intrusion and restore groundwater resources.

Environmental regulators should use 0.017 mcg/m3
as a screening level in their investigations.

Soil and groundwater cleanup goals should be strong enough to protect the air.

Development should be restricted wherever soil gas studies suggest that future indoor concentrations may
exceed the screening level. Where housing is approved, mitigation and notification should be required.

The remedy should be reconsidered at any site where vapor intrusion is recognized.

Trichloroethylene (TCE) is one of the top 8 percent most toxic compounds based on EPA Region 3 data. The data
available show that the current national debate over adequate vapor intrusion criteria is economic and not the result
of a lack of data. This is unfortunate given America’s past lessons involving lead and smoking, where we
ignored science for decades at the cost of many lives and young minds.

EPA has started addressing vapor intrusion, but investigation of this pathway is in its infancy. Furthermore, the
financial and technical expertise limitations at the state and local level will impact the Nation’s ability to
protect communities from TCE. Nevertheless, community members will try to apply political pressure where they
can to get adequate testing and remediation despite a regulatory process that is financially strapped, technically
challenged and conflicted. Some policies and regulations will be implemented to help, but this will take years and
will differ drastically from state to state. While communities work hard to bring this change, they will need the
support from political leadership to allow them to participate effectively. All participating agencies must involve
communities through HEART (Honesty, Empathy, Accessibility, Responsiveness and Transparency). Technical
issues needing to be addressed include: source definition, correlation of known contamination with records,
groundwater flow, soil gas data, indoor air data over time, biomonitoring, etc.

In the end, science must prove itself with empirical data from the affected communities, not just with modeling and
risk assessment. If the affected communities do not get this type of community involvement and technical support,
contamination will be missed, misjudgments will be made regarding true exposure levels, and the remedial actions
selected will fall short of protecting neighborhoods.

I am a resident in the Town of Union and co-founder of the citizens’ action group C.A.R.E. On
October 31, 2002 my daughter at the age of 17 during her senior year of High School was diagnosed
with Hodgkin’s Lymphoma.

On that same day in October the DEC, DOH, and IBM representatives agreed upon a mitigation decision matrix
to be protective of public health and to be used to determine which houses in my neighborhood, located in a
300-acre toxic plume, will be eligible for a mitigation system. To date there are 480 properties with mitigation
systems installed.

What about those properties that did not meet the criteria? People continue to live in their homes and work in
buildings that are contaminated with VOCs. They have chemical vapors inside and under their homes but
the levels are not high enough to warrant a mitigation system.

What about the family with small children living next door to a vented home? They are told they don’t
need testing because they are not in the plume, they just border it.

What about the home in the plume that has been tested, and VOCs are detected in the sub slab and indoor air.
They are denied a system, but their neighbors all have them.

What about the people that live within 100 feet of the plume, that are just plain scared? What type of standard is
available to protect them? They have every reason to be concerned. They are not eligible for testing.

There are hundreds of people in this community that share these same stories. What is worse, knowing or not
knowing? The level of fear and anxiety is the same for everyone living within this plume. Test or no test, system
or no system.

Think about the scenarios I just mentioned. They are real. There are about 200 more homes in the area near
the mapped plume that have TCE under them. They are not qualifying for testing or mitigation systems. The
only way we can ensure the safety of the people in this designated area is to lower the acceptable levels of TCE
vapor intrusion and vent their homes.

Based on this testimony I am here today asking that the EPA set a standard for TCE at nothing greater than .017
micrograms per cubic meter. It is your fiduciary duty to ensure that this community and every community nationwide
be protected from vapor intrusion stemming from soil and groundwater contamination caused by industries that
jeopardize our health and well being.

Some two years ago, my wife was diagnosed with squamous cell carcinoma, a cancer of the throat.
Oncologists will never venture any statement as to its cause, but it is generally thought to have origins
by inhalation of air or drinking of liquids (water). In an effort to determine what may have caused this
illness, I began to ask questions from a multitude of sources, such as the Cancer Society, the
NYS-DOH, and private oncologists. Needless to say, I was confronted with more questions than
answers. To my dismay, I found that there were no safe guidelines or standards that addressed
residential indoor air standards for toxic intrusions. Therefore, safe guidelines and standards
must be established to protect the citizenship of our community as well as other communities
around the country. These guidelines and standards must be put into place as soon as possible to
ensure productive and healthy lives for all.

It is crucial that a commission of scientists and medical personnel undertake extended studies for
low dose ingestion of toxins in humans without delay. Results of this toxic/human hypothesis of low
dose exposure must be made available to the general public at the earliest timeframe possible.

Pressure should be placed on EPA to have their science committees present the lowest possible
threshold level for remediation. While some scientists admit that any air/vapor TCE reading qualifies
to institute remediation, we must not accept any guideline threshold level higher than .175 micrograms
per cubic meter (a guideline of .017 micrograms per cubic meter would be preferable).

Remediation must be vigorously undertaken by any and all means at our disposal. However,
mitigation via venting systems installed in homesteads is, at best, only a temporary "stop-gap"
measure.

Last, and most importantly, I request that the following be given serious consideration: That in order to
expedite residential VOC/toxic testing by the NYS-DOH/NYS-DEC to determine toxicology levels:

Sub-slab testing alone be done to determine "hotspots" of TCE/PCE within
a given area, and that a reasonable guideline be determined as a threshold of concern.

Readings over and above the established sub-slab threshold be scheduled for further
comprehensive testing during the heating season.

As it now stands, a team of technicians must take an inventory of any and all items within a
basement to remove anything that would possibly influence air sampling. This elimination
process alone takes approximately four hours. Thus the team is able to test approximately
two residences per day. However, by performing sub-slab sampling, approximately six houses
could be accomplished per day. By reducing time, costs would likewise be reduced, and overall
area testing would be accelerated.

Donna Lupardo, Resident Action Group of Endicott (Edited by staff)

The residents of the Village of Endicott and surrounding entities have been exposed to contaminants from
multiple exposure routes including air pollution, contaminated drinking and bathing water, soil gas, and
vapor intrusion. Health studies need to take into consideration the combined effects of these various
exposure routes. In looking at places like Endicott, there is a need to create models that take all of these
routes into consideration.

As far back as 1989, reports were being published indicating that the IBM facility led the United States
in chlorofluorocarbon emissions and other pollutants. Most of us here are interested in knowing what
the current emission levels are from the plant; how the current ambient air is affected by hundreds of
venting units; and what we can learn from historic air emission levels. After much delay, the Agency for
Toxic Substances and Disease Registry (ATSDR) is now in the process of surveying residents to gather
information about the historic pre-1987 air emission levels where there seems to be some kind of
information gap.

We’ve now been witness to the evolution of the science of vapor intrusion. Communities
around the State are grappling with the reality of this new exposure route. I join my friends in saying
that we want the State to thoroughly examine the issue of putting in place stricter TCE air standards,
which should be stricter than the current standard of five micrograms per cubic meter.

Many of these standards are set for adults over short exposure time periods. We’re especially
concerned that the standards also take into consideration young children who are more sensitive to
contaminants of this kind.

I’d like to point your attention to something that our Press and Sun Bulletin reported back in
August. They reported that water samples from a well installed in the IBM cafeteria building back in
1963 showed evidence of pollution in the bedrock two hundred and fifty feet below the site and evidence
suggests industrial solvents may have reached a deep aquifer that feeds a network of wells along the
Susquehanna River Valley. Collectively these wells serve at least eighty thousand residents in Vestal,
Johnson City and in Endicott. Obviously, there could be a potential need for more aggressive
remediation efforts given the sheer number of people affected.

Finally, we are grateful that ATSDR has a mixtures work group investigating the water contamination
issue. While we’ve been assured that there are low levels of various compounds in the water,
what is not clear is what happens when these low levels interact with one another. Further scientific
inquiry may show that such commingling of these contaminants represents a potential threat to public
health.

I am a resident in Hillcrest, NY and part of a citizens’ action group, the Hillcrest
Environmental Action Team, HEAT.

In 1992, a discharge of TCE into a dry well at the former Singer-Link facility (now owned
by CAE Electronics) was mapped, indicating movement of this material into the surrounding
neighborhood. Since then, TCE has spread throughout portions of the residential area and
even shows up in a monitoring well 1700 feet from the source, on a direct path towards our
drinking water well field.

Recently, the DEC began monitoring TCE levels in our homes. Levels above 5 micrograms/cubic
meter were discovered. I had been following a similar problem in Endicott and was told that the
standard for mitigation there was 0.22 micrograms/cubic meter. In Endicott, just under 500 homes
were vented. In Hillcrest, only three homes were vented although many more were above the
.22 micrograms/cubic meter action level used in Endicott.

The EPA proposed guideline for TCE in residential buildings is 0.017 micrograms/cubic meter.
This is roughly 300 times lower, that is, more stringent, than the standard set by New York’s
DOH. Although the DOH acknowledges the range of estimates for TCE (for one excess cancer per
million persons) is 0.2 to 4 micrograms/cubic meter, our standard was set arbitrarily higher at
5 micrograms/cubic meter. The orders of magnitude difference between the provisional EPA
standard and DOH standard concerns me and many of my fellow residents.

I am also concerned that the venting of TCE from the subslab of our homes is moving the
pollutant from one area to the next. When temperature inversions form in these valleys, the air that
we are venting from the ground is trapped in the valley so not only are we breathing it in our homes,
we are breathing it in the outdoor air also. We find this unacceptable.

I would like the NYS Assembly to consider using its influence on the NYS Department of Health to
change the NYS standards for TCE in our homes to match the EPA provisional guidelines. I would
also like to see outdoor air standards set that are going to insure that breathing this air is safe for
our children.

Debra Hall, Hopewell Junction Citizens for Clean Water

All I know is that living in the United States, paying my taxes and living an honest life, the least my
family and I deserve is clean air to breath and clean water to drink. Imagine knowing that your water
and air are contaminated. You go to the health agencies, the so called experts, who are there to help
you. But instead of getting the help you need you get untruths and false information. And then you
ask why? Is it financial? Is it that if the person tells you what they know they will get in trouble? Is
it that they really do not know?

Whatever the reason is, my family should not be at risk of getting cancer or some other deadly
disease. I see it all around me, so many sick people, especially children. It has been known that
my site was contaminated since 1979, but the correct investigation never took place. The Hopewell
Junction Citizens for Clean Water ask to stop making us victims. Give us air standards that will
protect us. It can be done. It’s possible. No more excuses. The technology is here.
It’s only common sense that this issue gets dealt with correctly and morally.

TCE is an organic chemical that has been used for dry cleaning, metal degreasing and as a solvent for
oils and resins. It evaporates easily in the open air but can stay in the soil and groundwater for years
afterwards. In the body, TCE may break down into multiple other chemicals such as dichloroacetic acid,
trichloroacetic acid, chloral hydrate, and 2-chloroacetaldehyde. These products have been shown to be
toxic to animals and are probably toxic to humans, especially young children with developing bodies.

The most well-studied and significant health effect of TCE is its link to cancer. Studies of workers exposed
to TCE are sometimes complicated to interpret because many of these workers are exposed to other
solvents that also can cause health effects. However, TCE has been found to cause cancer in both mice
and rats, which suggests that it also causes cancer in humans. The World Health Organization has
classified TCE as a Class IIA carcinogen, meaning that TCE is probably carcinogenic to humans. The
EPA has also stated that TCE may have the potential to cause cancer in humans, and has set a maximum
contaminant level for TCE of five parts per million in drinking water.

Other effects that can result from heavy TCE exposure include damage to the liver, kidneys, gastrointestinal
system, and skin. TCE has been linked to birth defects. Chronic exposure to TCE can also affect the human
central nervous system. Case reports of intermediate and chronic occupational exposures included effects
such as dizziness, headache, sleepiness, nausea, confusion, blurred vision, facial numbness, and weakness.

For all of these reasons, all occupational exposures to TCE should be thoroughly investigated. Not only
do the workers who have been exposed to TCE deserve to know the potential health effects they have
suffered, but further research into the health effects of TCE will help clarify important questions that remain
about its health effects.

In addition, we also need to consider the effects of TCE contamination on people in the broader community.
For example, children are especially vulnerable to the health effects of TCE, just as they are to many other
chemicals. The health and economic consequences of children’s present-day exposures to
environmental toxicants will be experienced by our society throughout much of the twenty-first century.

Unfortunately, we have learned this lesson the hard way, in part because of exposures to chemicals such as
TCE. A very high rate of childhood cancers in Toms River, New Jersey was found to be linked to the amount
of drinking water that women ingested during their pregnancies. Even though the water was never found to
have levels higher than EPA’s contamination standard for TCE, the researchers’ analysis
demonstrated that exposure to TCE in the fetus was associated with cancer, especially leukemia, in these
children. The epidemiologists who studied this cluster of cancer suggested that the developing fetus might
be especially vulnerable to TCE and other chemicals that were found in the drinking water in Toms River. As
the exposure to TCE was removed, researchers found that the cancer rates in Toms River decreased
significantly.

One way to prevent and treat children’s exposures to environmental contaminants, such as TCE, is
through the development of a statewide system of Children’s Environmental Health Centers of
Excellence.

David Ozonoff, M.D., M.P.H., Professor of Environmental Health, Boston University School of
Public Health (Edited by staff)

I have had a long interest in the health effects of the chlorinated ethylenes TCE and its very close relative,
tetrachloroethylene (PCE), and have authored numerous peer-reviewed epidemiological studies on these
chemicals. TCE has been implicated in at least four kinds of adverse health effects: effects on the central
nervous system; cancer; birth defects; and autoimmune disease, such as lupus. For historical reasons
and force of circumstance much of our knowledge of the effects of TCE are based on occupational
exposures. While it is not easy to determine what effects might be expected, if any, at the substantially
lower levels normally encountered from vapor intrusion, I am concerned about effects even at these levels
for two main reasons.

First, we have been studying the effects of TCE in drinking water for almost 15 years and have seen
substantial increased cancer risks at exposures orders of magnitude lower than occupational exposures.
Residential exposures to drinking water come from a combination of ingestion, inhalation (from air stripping)
and dermal absorption, with the latter two being of roughly the same order of magnitude as ingestion.
The current maximum contaminant limit (MCL) for drinking water is 5 micrograms per liter. This
corresponds (roughly) to an indoor air exposure of 1 microgram per cubic meter of air. The MCL is an
old standard based on outdated cancer estimates. Thus the level of 5 micrograms per cubic meter
proposed by the NYS DOH is not consistent with the current (now fairly old) water standard.

In addition, there is reason to believe that the exposure level corresponding to an excess cancer risk
of one in one million is considerably lower than previously thought. To be health protective one normally
chooses the most conservative estimates. Considerable uncertainty in the correct parameter estimates
for important physiological processes, like the rate of absorption between species, can lead to very large
differences in dose-response modeling. W.J. Cronin and colleagues use Monte Carlo analysis in
conjunction with physiologically-based pharmacokinetic (PBPK) modeling to determine the impact of
different parameter values on estimates of the risks posed by TCE. There is a wide range of legitimate
estimates using PBPK models when coupled with the linearized multistage model used by DOH. Cronin,
for example, has estimates as low as 0.02 micrograms per cubic meter as the one in one million risk for
TCE in air.

The choice of a linearized multistage model, as used by DOH, is not the only possible choice, and
choosing a different biologically plausible model can result in a large variation in estimated risks. C.R.
Cothern and colleagues investigated the variations between four different models, including the model
chosen by DOH. The difference in estimated risks among the models was almost a factor of 10,000, i.e.
the most protective model (the Weibull model) predicted risks from TCE in drinking water to be 10,000 times
higher than the risks from the least protective model (the multistage model chosen by DOH). There are no
biologically based criteria for choosing one model over another.

My second concern is that adverse health effects can be expected to result from extremely tiny exposures
where some kind of biological amplification of damage occurs. The classic example is cancer, where a
tiny alteration in DNA makes a cell into a cancer cell. The original damage is biologically reproduced and
the offending tiny amount of chemical no longer need be present. This is essentially the reason we believe
there is some cancer risk at every level of exposure.

There are other biological systems where such intrinsic amplification might be expected, including the
immune system (eg. bee stings and the dramatic, sometimes fatal effect of tiny exposures); the nervous
system (where tiny signals are amplified into large responses); and human reproduction (where an entire
organism comes from a single fertilized egg). Thus the health effects seen in occupational environments
are plausibly present, although at a much lesser frequency, at much lower exposures as well.

I have been studying the health effects of TCE for about 8 years and am increasingly concerned about the likely
carcinogenicity of TCE and its impact on the health of those exposed to even low levels of this chemical.

In 1997 I was awarded a grant by the EPA to evaluate the epidemiologic evidence for making inferences of
cancer hazards and risks for exposure to TCE. With colleagues, I conducted a detailed review of more than
80 relevant scientific publications. We concluded that evidence of excess cancer rates among occupational
cohorts with the most rigorous exposure assessment is found for kidney cancer, liver cancer,
non-Hodgkin’s lymphoma, cervical cancer, Hodgkin’s disease, and multiple myeloma.
In 2000, I again summarized the data and made similar conclusions. One notable report published since
my review in 2000 was on a new cohort in Denmark that uses measures of biological material to document
exposure to TCE. In general, the results of that study provided additional support for the findings we
presented in 2000, which suggested that TCE exposure causes cancer in humans.

I acknowledge the limitations of some of these studies, and imprecision of the assessments of exposures,
but I believe that the evidence points strongly towards carcinogenicity and that exposure should be minimized
to the degree reasonably possible unless and until evidence to the contrary can be developed. In short, based
on the evidence, we believe that TCE should be considered a human carcinogen until proven otherwise.

In general, any exposure to a carcinogen increases an individual’s risk of developing cancer. Therefore,
on the basis of the available evidence, and in the interest of preventing unnecessary cases of cancer, I urge you to
limit exposures to the minimum amounts reasonably achievable.

Because the studies conducted did not collect sufficient data on length and magnitude of exposures for
rigorous modeling of the likely carcinogen, we should err on the side of overprotection rather than underprotection.
In addition, the research on other outcomes is somewhat limited, again suggesting the need for more stringent
rather than less stringent exposure limits.

Conclusions and Recommendations

The evidence gathered through this hearing underscores the high level of uncertainty and controversy
associated with all of the issues raised by vapor intrusion including the screening and testing of sites,
the setting of indoor air quality standards, and determining the appropriate mitigation, and remediation
measures. Policies and guidelines to address these issues are still in the developmental stage in New
York State and across the country.

An overarching principle to remember as New York proceeds to address the challenges posed by
vapor intrusion is that the degree of uncertainty associated with these challenges is an issue in itself.
Living with uncertainty is one of the most difficult aspects of living at a contaminated site. It is a source
of incredible stress and frustration. This uncertainty is a given, at least for the foreseeable future. In the
face of such uncertainty, government must strive to take a precautionary and transparent approach.

A precautionary approach holds that where threats of harm to human health or the environment exist,
lack of full scientific certainty about cause and effect should not be viewed as sufficient reason for
government to postpone precautionary measures to protect public health and the environment. We
must use the knowledge we have today to take a preventive approach to eliminating exposures from
vapor intrusion.

Government must also provide citizens with complete and accurate information on the potential health
and environmental impacts associated with different policy choices. The policy making process should
be open and transparent, and provide citizens with opportunities for meaningful participation.

In addition, the degree of scientific complexity associated with a decision should not be used to obscure
the nature of the decision at hand. For example, the scientific evidence regarding TCE supports a range
of toxicity estimates, largely based on the protectiveness of underlying assumptions. This has led to the
adoption of indoor air guidelines by EPA Regions and states that vary by an order of magnitude or more.
These guidelines are all scientifically plausible and supported by "sound science." The
choice between them is largely a policy choice, not one of science alone.

The following recommendations are based on information gathered through this hearing. These actions
should be taken as part of developing a comprehensive policy for addressing vapor intrusion in New York
State:

DOH should revise its TCE Guideline to reflect the most protective (i.e. conservative) assumptions
about toxicity and exposure supported by science. Where uncertainty exists, DOH should err on the
side of protection. The TCE Guideline should correspond with an excess cancer risk of one-in-one-million
as required for the development of soil cleanup standards under the BCP, based on these conservative
assumptions. Also as required in the BCP, the Guideline should be protective of sensitive populations,
especially children, and take exposure from multiple sources and routes into account. In addition, the
Guideline should be fully protective (corresponding to a hazard index of one) for all non-cancer health
effects as identified by the Department in its own risk assessment.

Residents living adjacent to or near a contaminated site with a potential for vapor intrusion, but
outside the perimeter of the area that has been designated to be tested, have legitimate concerns
regarding whether contamination is present in their homes. At a cost of two thousand dollars or more,
testing represents a large cost to these residents but only a small percentage of the overall cost of
cleaning up the site by the responsible party or the state. In such instances, DEC and DOH should
test the indoor air of any resident who requests such a test.

DEC should continue to review and improve the methods used to screen and investigate sites,
including sampling during all seasons of the year and taking into account preferential pathways.

DEC should take steps to protect ambient air quality at vapor intrusion sites, including the adoption
of requirements that would limit the emission of contaminants to ambient air from indoor air
mitigation systems.

When development is approved at sites with the potential for vapor intrusion problems, long-term
monitoring and mitigation should be required. In addition, potential owners, tenants, and other
long-term users of the site should be notified of the potential for vapor intrusion problems prior to
sale or entering into a contract.

Once direct exposures have been mitigated, focus should be placed on cleaning up the source of
vapor intrusion, i.e. soil and groundwater contamination, as quickly and aggressively as possible.
DEC’s view of mitigation as a short term solution and their stated intention to ensure that
steps are taken to remediate soil and groundwater and eliminate the source of hazardous vapors
should be strongly supported. Furthermore, in promulgating generic soil cleanup standards
pursuant to the BCP statute, DEC, in consultation with DOH, must take vapor intrusion into
consideration.

New York State is in the beginning stages of developing policies to address vapor intrusion and should
work with citizens and public policy makers to tackle the important challenges ahead in addressing the
threat to public health posed by vapor intrusion. This hearing was one effort to provide transparency and
encourage participation.

APPENDIX A

ASSEMBLY STANDING COMMITTEE ON ENVIRONMENTAL CONSERVATION

NOTICE OF PUBLIC HEARING
Oral Testimony by Invitation Only

SUBJECT:

Vaporization of contamination from soil and groundwater into indoor air

PURPOSE:

To examine the human health impact of vapor intrusion stemming from soil and groundwater contamination

Chapter 1 of the Laws of 2003 establishing the Brownfield Cleanup Program (BCP) provided for the refinancing
of the State Superfund program and a comprehensive program for the long-term restoration of groundwater. The
groundwater provisions of the new program are based on experience at various sites under New York’s
Superfund and Oil Spill cleanup programs. The intent was to address the shortcomings of those programs by
providing for the investigation and pursuit of off-site migration of contamination, particularly through groundwater
plumes, in order to eliminate human exposure.

The vaporization of contaminants from soil and groundwater impacting indoor air has occurred at several
State Superfund sites and has the potential to be a problem at brownfield sites. While both the New York
State Department of Environmental Conservation and United States Environmental Protection Agency are
considering draft guidance that sets standards for vapor intrusion, neither agency have issued final guidance.
Vapor intrusion should also be considered during the development of generic soil cleanup standards under the
BCP.

The purpose of this hearing is to examine issues concerning the vaporization of contamination from soil and
groundwater and resulting human exposure, and to determine what lessons can be learned from experience
in order to properly address vapor intrusion in the future. The Committee will take testimony from various
witnesses including panels of federal, state and local government officials, public health and environmental
experts and citizens representing affected communities.

Oral testimony will be accepted by invitation only and limited to 5 minutes duration. 10 copies of any prepared
testimony should be submitted at the hearing registration desk. The Committee would appreciate advance
receipt of prepared statements. Written testimony will also be accepted and may be sent to the contact person
listed on the reply form. In order to further publicize the hearing, please inform interested parties of the
Committee’s interest in receiving written testimony from all sources.

In order to meet the needs of those who may have a disability, the Assembly, in accordance with its policy of
non-discrimination on the basis of disability, as well as the 1990 Americans with Disabilities Act (ADA), has
made its facilities and services available to all individuals with disabilities. For individuals with disabilities,
accommodations will be provided, upon reasonable request, to afford such individuals access and admission
to Assembly facilities and activities.

On November 15, 2004 the New York Assembly Standing Committee on Environmental Conservation will hold a
public hearing to examine issues concerning the vaporization of contaminants from soil and groundwater into
indoor environments and human exposure to such contaminants. Specifically the Committee is interested in
receiving testimony addressing both the state of the science and as well as the policy implications of vapor intrusion.
You are invited to appear before the Committee on this date to more formally explore these issues.

Witnesses participating in the hearing may be grouped into panels consisting of individuals with similar backgrounds
and/or expertise. Each witness will be asked to make a formal presentation for 5 minutes, followed by questions for the
panel as a whole, as well as for individual witnesses.

The hearing will be held on November 15th at the Endicott Visitor Center in Endicott, New York and will begin at
11:00 a.m. More detailed information is included in the enclosed Hearing Notice. Your response by
November 4, 2004 will be appreciated. If you have any questions, or would like further information, please contact
Jeff O’Donnell or Alex Roth at 518-455-4363. Thank you and we look forward to hearing from you.

Sincerely,
Thomas P. DiNapoli
Chair, New York State Assembly
Committee on Environmental Conservation

Thank you for the opportunity to comment on the Department’s proposed vapor intrusion policy. I
appreciate that the Department has acted quickly in drafting this policy in an area that experts in environmental
health and engineering have only recently come to realize has significant potential to result in significant risks to
human health from exposures.

As you know, the Assembly’s Environmental Conservation Committee recently held a hearing on vapor
intrusion in Endicott, NY. The difficulty associated with setting indoor air quality standards underscores the need
to proceed cautiously, yet to ensure that actions taken protect the health of residents. Testimony from citizens
impacted by contaminated sites here in New York made it clear that living with uncertainty is one of the most
frustrating and stressful things about living near a contaminated site.

The vapor intrusion policy being formulated by the Department has the potential to ease much of this stress and
frustration. To be successful, the vapor intrusion policy that is finally adopted by the Department must be protective
of human health and the environment and be transparent. People must be able to see and understand why the
Department has made the decisions it has in ranking and investigating contaminated sites.

It is with recognition of the great work being done and tremendous efforts being put forth at the Departments of
Environmental Conservation and Health to develop a protective vapor intrusion policy as well soil cleanup program
and standards that I offer the following comments. I encourage DEC to consider them and re-issue another draft
before finalizing this policy.

Sincerely,
Thomas P. DiNapoli
Chair, New York State Assembly
Committee on Environmental Conservation

Assemblyman Thomas P. DiNapoli
Comments on
New York State Department of Environmental Conservation’s
Draft Policy
DER-XX/Evaluating the Potential for Vapor Intrusion at Past, Current and Future Sites.

Thank you for this opportunity to comment on the Department of Environmental Conservation’s (DEC’s)
Draft Policy on Vapor Intrusion. DEC’s intention to evaluate all contaminated sites to determine whether the
vapor intrusion pathway is complete is commendable. I am also looking forward to reviewing the draft "Guidance
for Evaluating Soil Vapor Intrusion in the State of New York" when it becomes available.

While I commend DEC for issuing this draft policy is such timely manner, I believe that there is a lack of transparency
that makes it impossible to assess fully the adequacy of the policy as a whole and its specific components. I hope
that the following comments will be useful in focusing attention on areas that need additional explanation.

The Draft Policy Needs to Clarify How Many Sites will be Investigated and the Timeline for Investigation. Page
two of the Draft Policy states that DEC estimated that solvents or other volatile chemicals have been disposed of at over
750 sites resulting in contaminated soil or groundwater. Page three notes that there are more than 400 sites where
chlorinated volatile organic compounds (CVOCs) were disposed of or detected in soil or groundwater. The draft report
states a "manageable number of sites" will be initially targeted for further study to determine whether impacts
associated with vapor intrusion exist. Once initial investigations are complete and any necessary revisions to the
procedures are made, DEC will then begin to investigate the remaining sites identified as having potential vapor
intrusion impacts. Each year several previously investigated sites will be selected from each Region for further vapor
intrusion investigations until all sites requiring further study have been completed.

There is concern that it will take DEC a very long time to investigate all known sites at which public health threats may
exist. DEC should state what it believes to be a manageable number of sites that will be targeted initially for further study,
and identify how long it estimates it will take to investigate all sites that may be causing vapor intrusion problems.

The Draft Policy needs to state the trigger for actual investigation of contaminated sites. While the summary of
the draft policy notes that all past, present and future contaminated sites will be evaluated, the section on screening
criteria (p.3) notes that sites will be prioritized based on the ranking and considered for further evaluation. Due
to the uncertainties that exist in assessing vapor intrusion, the fact that site characteristics determine how vapors migrate
and that understanding of soil vapor migration and intrusion is still evolving, I believe that on-site inspections will be
necessary at all sites. In addition, DEC should state clearly whether it intends to investigate all sites or some percentage
of sites and what actions will be taken when vapor intrusion impacts are found to exist.

Additional Public Outreach Needed
Sites with vapor intrusion may have a significant public health impact. There should be an opportunity for public input
after DEC completes the proposed list for further investigation.

Numerous Questions Remain Concerning Complete Pathways
According to the draft policy, a complete pathway means that humans are being exposed to vapors that originate from site
contamination. For sites determined to have a complete pathway, further evaluation is necessary to determine whether the
pathway poses a potentially significant risk to human health and whether interim or long-term mitigation or remedial
measures are necessary. For sites at which it is determined that a vapor intrusion exposure pathway does not exist
under current conditions, a vapor intrusion pathway must be considered if future plans for the site include development
that could result in a complete exposure pathway. I commend DEC for planning to incorporate future development plans
into this policy.

It is not clear how DEC will determine the current location and extent of the groundwater plumes, which is necessary to
determine completed pathways. Without this information, it is impossible to establish a safe distance for measuring
adjacent site use or for determining what structures should be evaluated for completed pathways - as is called for in
the draft policy. This needs to be clarified.

While this policy deals directly with existing vapor intrusion problems, I am also concerned with how DEC will address
situations where no complete pathway is currently identified, but migrating groundwater with levels of contamination
exist that may ultimately result in vaporization problems when the plume reaches inhabited areas. If DEC will be relying
on existing, dated, information on sites, an additional concern exists as to how DEC will ensure that new pathways
have not developed/evolved over time.

As defined, a complete pathway means that humans are exposed to vapors that originate from site contamination.
By this definition, vapor intrusion is not limited to indoor air. I support the inclusion of outdoor vapors from contamination
being incorporated into DEC’s vapor intrusion policy.

Prioritization of Contaminated Sites Needs More Explanation
The draft policy lacks necessary information explaining how and why decisions were made in developing the process
for soil and groundwater screening for vapor intrusion and site ranking. This lack of information makes it impossible to
evaluate fully the appropriateness of such screening and ranking.

According to the draft policy, prioritization of contaminated sites will drive additional investigation. It is not clear how
DEC will determine if impacts associated with vapor intrusion exist. DEC should clarify how many site-specific
conditions and what numerical weighting they believe will have to be present to trigger further action. Will one completed
pathway be sufficient to trigger additional investigation?

It Is Unclear Why Soil and Groundwater Contamination are to be Prioritized Separately
The rationale for DEC’s plans to prioritize soil and groundwater contamination separately is not clear. Is there
something inherently different about the contaminated soil and contaminated groundwater in relation to vaporization that
require separate ranking?

Additivity should be Considered
If DEC proceeds with separate prioritization of soil and groundwater contamination, the methodology should allow for
consideration of additive effects at sites that have multiple types of contaminated media. Additivity should also be factored
in for cases in which there is more than one type of contaminant known to have adverse health affects. For sites with multiple
complete pathways, each known or suspected completed pathway should be counted as additional weight for ranking.

Lack of Information Should Not be Assumed to Mean No Impacts Exist
One of the acknowledged problems associated with vapor intrusion is that it is not possible to know how vapors will travel
underground. Preferential pathways can be accorded additional weight if they are known, but many times such pathways
are not known or even suspected before indoor air is tested. Consequently, the lack of known preferential pathways should
not take away from the ranking of any site.

Screening for Chlorinated Volatile Organic Compound (CVOC) Vapor Intrusion
It is not clear why DEC selected the contaminant concentrations or depth to groundwater levels it did for site screening.
An explanation needs to be provided as to why the site-specific conditions to be evaluated were selected, why the
contaminant levels and depths to groundwater were determined appropriate, and how the weighting factors were
selected.

Concern that Potentially Significant Sites Will Not Triggering Action
In 2003, the Department of Health conducted seminars on the development of soil contamination criteria. At the seminar
held in Albany, DOH personnel noted evidence of unacceptable levels of vapor intrusion being experienced at places
where groundwater contamination met state standards. In the proposed ranking for groundwater contamination, the
lowest level of contamination (<10ppm) in the screening table receives a weight of 1, the lowest weight possible. Many
CVOCs and VOCs have an MCL lower than 10 ppm in groundwater. This raises concern that sites posing potential health
risks may be ranked in such a way that further site investigation for vaporization impacts is not conducted.

The Trigger for Further Investigation at Sites with Contamination Deep Underground Needs Further Explanation. The
background section of the draft policy notes that past assumptions that drove investigation into vapor intrusion were
flawed, including the assumption that if an off-site dissolved contaminant plume flowing beneath a home or business
was deep, then the concentration of vapors entering buildings above would be so low that they would not represent indoor
air concerns. As drafted, this policy places the lowest possible weight on sites where contamination is deep underground.
This seems to be inconsistent with DEC’s acknowledgement that the potential impacts of such contamination were
previously underestimated. It is unclear that the proposed weighting of depth to groundwater proposed in this policy will
provide adequate protections for human health. An explanation of how this determination was made needs to be provided.

Information is Needed for Sites with Source Remediation Complete and Remaining Groundwater Contamination.
The section on vapor intrusion investigation does not cover those cases in which the initial source of contamination
has been remediated, but contaminated groundwater remains either on or off-site. The draft policy notes (p.5) that if
groundwater within 100 feet of or beneath an occupied building is contaminated with VOCs, then a characterization effort
will be required. If groundwater quality data is unavailable, a limited groundwater investigation may be required to evaluate
current groundwater conditions downgradient of any remaining on-site sources of VOCs in order to make this determination.
DEC needs to ensure that sites where the source has been remediated but groundwater remains contaminated are covered
in its final policy.

Additionally, for sites at which groundwater contamination has existed for some time, contaminated groundwater plumes
may have migrated further than 100 feet from the original source. Provisions for addressing this should be included in the
draft policy.

The screening tables each have four levels of contamination. DEC should explain why these levels were selected.
Are there different health impacts associated with exposure to VOCs/CVOCs for the different levels selected?

Is the smallest contamination level selected for weighting associated with lifetime cancer risks of one in a million,
or a hazard index of one? If not, what criteria would result in such a measure?

DEC should explain why it decided to treat all VOCs/CVOCs equally. The MCLs for drinking water differ significantly
for various VOCs/CVOCs, and research shows that the health effects differ; some are known carcinogens while
others may not to be. An explanation should be provided as to why the proposed policy does not reflect the differences
known about various contaminants.

For different soil types, clay is ranked lowest. On Long Island, it has been shown that contamination may accumulate
on top of, or be sorbed into, clay lenses and be a source for vapor migration in soil gasses. Has this scenario been
factored into DEC’s ranking?

The groundwater screening allows an additional point for the presence of NAPL. This should be expanded to include
potential NAPL. It is very difficult to confirm the presence of NAPL, but the potential for NAPL exists when contamination
exists at certain levels. In such cases, DEC should award additional points.

Sites with sensitive receptors, such as children who are significantly more susceptible to contaminants than adults,
should be evaluated more quickly than sites without sensitive receptors and should be remediated accordingly.

As currently drafted, the middle two categories on both the CVOC table and the Depth to Groundwater ranking table
overlap numerically (10 — 100 ppb and 100 — 500ppb, and 15 — 50 feet and 50 — 100 feet).
This should be corrected to allow for consistent ranking.

Conclusion

I hope these comments are useful in formulating a final, transparent vapor intrusion policy. If you have any question,
please feel free to contact my office.